The present invention relates to a magnetic recording and reproducing apparatus and a method for accessing magnetic tapes using the apparatus. More particularly, the invention relates to a tape streamer to which data in such devices as servers are backed up. The inventive apparatus and method involve unloading a magnetic tape from a tape streamer after the tape is positioned to one of its unloading regions which is located approximately in the middle of a lengthwise tape area where user data have been recorded. Such unloading regions are located at predetermined intervals along the magnetic tape. The inventive apparatus and method also involve permitting selection between two unloading regions to which the magnetic tape is positioned before being unloaded from the tape streamer. One of the two regions is located approximately in the middle of the user data-packed tape area, the other region designated by a host device. This manner of unloading a magnetic tape allows a desired file recorded thereon to be accessed significantly faster than conventional methods of tape unloading.
Tape streamers conventionally establish an unloading region at the beginning or the end of each magnetic tape on which data have been recorded with high density. The magnetic tape is positioned to its unloading region before being loaded or unloaded to or from the streamer so that the data-packed tape will not be damaged in other sensitive areas during the loading or unloading process.
However, to load or unload a magnetic tape positioned to its unloading region at the beginning or end of tape requires that the tape be wound up to its beginning or end in advance. After recording, it takes time to wind up the tape all the way to get the tape cassette ready to be ejected. It also takes time to load a tape cassette into a recording and reproducing apparatus and fully wind up the tape before actually proceeding to record or reproduce data to or from the tape. In order to circumvent such disadvantages, some tape streamers have been proposed which establish unloading regions at locations other than the beginning or the end of tape. With this kind of tape streamers, the magnetic tape may be unloaded as positioned to its nearest unloading region.
Having studied conventional and related structures, the inventors of this invention envisioned a novel tape streamer and a method for operating it whereby a desired file on a magnetic tape would be accessed much faster than by conventional setups.
The present invention has been made in view of the above circumstances and provides a magnetic recording and reproducing apparatus permitting significantly faster access to desired data storage locations than its conventional counterparts.
In carrying out the invention and according to one aspect thereof, there is provided a magnetic recording and reproducing apparatus for positioning a magnetic tape to one of unloading regions thereon which is situated adjacent to a substantially intermediate point between an end of recorded user data and a beginning of the recorded user data along the magnetic tape, before unloading the magnetic tape thus positioned into a tape cassette. This structure minimizes mean access time.
According to another aspect of the invention, there is provided a magnetic recording and reproducing apparatus which, in a first operation mode, positions a magnetic tape to one of unloading regions thereon which is situated adjacent to a substantially intermediate point between an end of recorded user data and a beginning of the recorded user data along the magnetic tape, before unloading the magnetic tape thus positioned into a tape cassette; and which, in a second operation mode, further positions the magnetic tape to one of the unloading regions thereon which is designated by an external device, before unloading the magnetic tape thus positioned into the tape cassette. This structure also minimizes mean access time in different operations modes of unloading.
Other objects, features and advantages of the invention will become more apparent upon a reading of the following description and appended drawings.